Formation of emulsions comprising oil and water commonly occur in the extraction, production and processing/refining of petroleum oil. It is often necessary to separate the water from the oil in order to effectively prepare the oil for further processing and/or refinement. A plethora of demulsifiers are known in the art for removing water from such emulsions. Demulsifiers are typically composed of one or more surfactants dispersed in a solvent system and may be derived from alcohols, fatty acids, fatty amines, glycols and alkylphenol condensation products, for example.
The ecological impact of offshore crude oil extraction has been subject to increasing scrutiny. Several international and national environmental regulatory agencies have determined that demulsifiers containing nonylphenol alkoxylates and related compounds have a deleterious effect on the marine environment. Moreover, conventional demulsifier chemicals typically do not meet a biodegradation level of greater than 20% as established by these regulatory agencies. Consequently, the likelihood exists that a vast majority of conventional demulsifiers will be banned from offshore use in the near future.
A need therefore exists for petroleum oil demulsifiers with an improved environmental profile. In particular, a need exists for environmentally friendly water-in-oil demulsifiers that are biodegradable and have a low toxicity in the marine environment.